Sparking device for internal-combustion engines.



G. HONOLD.

SPARKIHG DEVICE FOR INTERNAL COMBUSTION ENGINES. APPLICATION mum JULY 29, 1910.

1,105,659, Patented Aug.4,191 L 3 SHEETS-"SHEET 1.

G. HONOLD. SPARKING DEVICE FOR INTERNAL COMBUSTION ENGINES.

APPLICATION FILED JULY 29,1910.

1,105,659. Patented Aug. 4, 1914,

3 BBEETS-8HEET 2.

G. HONOLD.

SPARKING DEVICE FOR INTERNAL COMBUSTION ENGINES.

APPLICATION FILED JULY 29, 1010. 1,105,659. Patented Aug/1, 1914,

' 3 SHEETS--SHEET 3.

PATENT UFFICE.

GOTTLOB HONOLD, 0F STU'ITGART, GERMANY, ASSIGNOR TO THE FIRM OF ROBERT BOSCH, OF STUTTGART, GERMANY.

ll, 105,4 it).

Specification of Letters Patent.

Patented Aug. 4, 1914.

Application filed July 29, 1910. Serial No. 574,420.

To (1H whom it may concern Be it known that l, (lorruon lloxonn, engineer, a subject of the German llltlPtlOl, residing at 1lli llo znlauslrassc. Sloth gart, (lernmny. have invented certain new and useful Improvements in Sparking Devices for Internal-Colnbustion Engines; and l do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to sparking devices -for internal combustion engines, and particularly to what are known in the art as sparking-plugs, that is to say. devices embodying a plug prope adapted to be screwed or otherwise inserted into the wall of the engine-cylindcr and carrying fixedand 1nov able sparking terminals, and an electro-mag net coil provided with a suitable core and pole-piece for which the movable sparlv'ing terminal serves as an armature.

The object of the invention, in addition to realizing a simplt and economical construction, is to permit of the ready removal of the armature terminal fronrthe plug. for purposes of substitution or repair. without the necessity of removing the plug proper from the cylinder, and, in some instances. without the necessity of removing or displacing the electromagnet coil. The construction and arrangement of the parts is likewise such that not only is a good conducting connection maintained between the magnet coil winding and the armature terminal, but also that the interior of the coil is securely sealed against the pcnetratitm of the gaseous products of combustion from the cylinder.

The characteristic features of my invention are illustrated. in a number of ditt'erent forms or exemplitications, in the accompanying drawings, all of which illustrate the movable armature tcrminal as guided to move longitmlinally or axially by the at traction of the electro-magnct coil. as against tension of a spring. which spring normally tends to hold the movable terminal in good conducting contact with the fixed terminal.

In the drawings,

Figure 1 represents, in longitudinal section, a sparking device embodying my invention. and wherein the pole piece govern ing the armature is shown as integral with the elcctro magnet core. Figs. 2 and 3 represent like vicws of other forms or modifications of my invention, ditl'ering slightly in detail from each other, wherein the pole piece is shown as separate from the core, and wherein the spring connects the pole piece and armature terminal to form a composite entity. Figs. 3, 4 and 5 represent like views of other forms or exemplitications of niy invent-ion, wherein the ,pole piece and ar1nature terminal may he removed withoutdisassembling the magnet coil from the plug proper and without listurbing either of the latter. Fig. t' represents, partly in elevation and partly in section, the spring conncctcd removable pole piece and armature terminal, disassembled from the remaining parts of the device.

Similar letters of reference indicate simi lar parts throughout the several views.

The plug proper a is adapted to be inserted in the cylinder wall of the engine in any usual or preferred way, as, for instance, by screwing it into place, for which pur pose it; may be provided with a screw threadcd shank, as shown. It carries the fixed ter minal c, and the axially movable terminal a, the latter being contained within a guide tube (1, which is insulated from the plug 11. by means of the porcelain or steatitc insert The sleeve (7 may serve as a convenient means for carrying the electro-magnet coil 7), which may be screwed thereon, as shown,

so as to be removable in disassembling the parts. In the construction shown in Figs. 1,4 and 5, the pole piece of the core It is formed integral therewith, whereas, in the construction shown in the remaiitiing figures, the pole piece is shown as an individual element 9 separate from the main body portion of the core. The upper end of the axially movable armatureterminal c carries a spring This spring may engage a groove 0', as shown in Figs. 1, 9, 4. 5 and 6, or it may be screwed upon a scrmv-threaded projection of the armature terminal 0, as shown in Fig. :3; and, in either case. it may be further secured in place upon the armature terminal 0 by soldering.

In the form shown in Fig. l, the upper portion of the spring i enters a recess formed around the integral pole piece 9, and. in the construction shown in the remaining figures, the upper bortion of the spring 1' surrounds the lower portion of the separate pole piece g and may, if so desired, be soldered thereto.

Tn '3, both the upper portion of the armature terminal 0 and the lower portion of the separate pole piece g are shown as screw-threaded, this construction permitting the spring to engage the screw-threads, and this connection may be made the more se cure, if desired, by soldering the corresponding convolutions of the spring to the screwthreads with which they engage.

in order to prevent undue friction, when the armature terminal 0 slidesin the sleeve (5, a ring 70 of some hard material, such as steel, is inserted in the lower end of the sleeve d, the internal diameter of the ring being somewhat smaller than that of the sleeve, so that, when forced into place, it will securely maintain its position. The upper end of the armature terminal 0 is carried by the spiral spring 2'. This method of guiding the armature terminal 0 is of especial advantage when the sparking plug is arranged horizontally in the cylinder of the engine.

In order to maintain a good contact between the armature terminal 0 and the fixed terminal e and to regulate the stroke of the armature terminal 0, notwithstandinguthe continuous wear caused by the action of the sparks and the corrosion due to the products of combustion, annular disks Z (see Fig. 4) of metal or other suitable material may be interposed between the upper end of the sleeve (Z and the pole piece end of the core, so that, by removing these disks, one by one, as the armature terminal 0 wears away, the magnet may be screwed farther down on the sleeve, to attain the desired end.

F or the purpose of obtaining a tight seal between the interior of the cylinder magnet coil 6 and the interior of the plug, so that the products of combustion from the cylinder may not enter the interior of the coil, a cylindrical projection m is provided for the pole piece, which projection enters the guide sleeve rZ, whereupon the lower surface n of the pole piece presses firmly against the upper edge of the guide sleeve (Z, or against the intermediate disks Z, as the case may be.

The'sparking plug can be taken to pieces with ease for the purpose of exchanging worn parts for new ones, in the following manner: in the construction shown-in Fig? 1 the fixed pole piece 9 is integral with the magnet core 72, so that when the magnet coil is screwed off the sleeve (Z, the core with its pole piece remains in the magnet coil and the armature terminal 0 and spring 2' are exposed and can easily be removed from the guide casing (Z without the necessity of removing the plug a from the cylinder.

In the construction shown in Figs. 2 and 3 the pole plece g is only mechanically attached, as, for example, by riveting, solder-- ing or the like, to the spring a which is sim internal combustion engines,

part of the spring and armature, while g netically it belongs to the magnet core it [after the magnet coil has been unscrewed from the sleeve (Z, the pole piece 9', spi'i i and armature c are accessible and can eas'ly be removed.

In the constructions shown in Figs. 1, 2 and 3, when the magnet coil is screwed. on to the sleeve cl, the pole piece is thereby pressed against the upper edge face of sleeve, thus making a tight joint therewith, The construction shown in Figs. d and. 5, in which the pole piece 9, the sprir a and the armature terminal 0 are conn l as described with reference to Fig. 53,

are mainly differentiated from that already described, in that it is not necessary tin-- screw the magnet coil from the plug in order to remove the armature terminal, "z shown in Fig. l, the core 7?, with piece 9 and the armature 0 may be when the screw 0 has been unscrew Fig. 5 the core having the pole piece ,7 an is itself screw threaded at its upper end,

and is screwed into the bobbin of the mag net coil a. In this case, also, the pole piece 9, spring 2' and armature terminal 0 are shown as forming a composite entity, These parts may, however, be separately inserted.

The sparking device operates as follows: Une pole of the source of current is con-- nected to the metalliolbody of the engine, and is therefore in electrical connection with the plug a; the other pole is connected with. the magnet coil 5. Ate suitable inst at, the current traverses the coil, one end whereof is in electrical connection, with the armature terminal 0, which is insulated from the plug a. As long as "he magnet is without current, th terminal a is held by the spr the terminal 6 and the circuit through the coil, armature terminal plug a. As soon as a our .t in sent through the coil, the armature c is attracted by the pole piece 51' the action of the spring i and contact be tween 0 and e is broken, producing the ignition spark,

Having thus described my invention, what I claim is:

1, In a sparking device for cylinders of an electromagnet coil, a plug insertible in the cylinder and spaced apart from the coil. a contact terminal carried by the pl n axially movable armature termiualfproj cting within said coil and normally coiitacting with said contact terminal, a sleeve loosely surrounding the armature terminal and holding a coil in fixed relation to the plug, and a guide ring of rounded crosssection forming a substantially frictionless guide for the urnmture terminal; substantially as described.

in :1 sparking device for the cylinders n? inter-uni combustion engines, an axiallymnvnhle armature terminal, a pole-piece therefor, and a coiled spring connecting the urnmljure terminal with the pole-piece, hut nornmlly holding them out of contact with each other, said spring engaging 10 threads formed upon the terminal and pole- GOTTLOB HONOLD.

Witnesses M. ANscuiiTz, N. VEITH.

Copies of this patent may' be obtained for five cents eaeh, by addressing the Commissioner of Patents,

Washington, D. C. 

